Comparison Of Uvulo-Glosso-Pharyngeal Dimensions Between Different Vertical Skeletal Facial Patterns

Abstract

Background: The relationship between pharyngeal airway and dentoskeletal structures have been reported in various studies. Objectives: The aim of this study was to evaluate the uvuloglossopharyngeal dimensions in various vertical patterns in skeletal class I subjects. Methodology: The study sample consisted of pre-treatment Lateral cephalogram of 135 subjects (63 males and 72 females, aged 14-21 years) with skeletal class I pattern which were divided into three groups of normodivergent, hypodivergent and hyperdivergent facial patterns with 45 subjects in each group. The inter-group statistical comparison across the three study groups was done using Chi-Square test and the inter-group statistical comparison of medians was done using Kruskal-Wallis H test [non-parametric analysis of variance (ANOVA)]. Results: The distribution of median for upper airway such as SPAS, MAS, IAS, VAL did not differ significantly across three study groups (P-value>0.05 for all). The vertical position of hyoid bone (HH1) was significantly lower in Group 2 compared to Groups 1 and Group 3 (P-value<0.05 for both) and the anteroposterior position of hyoid bone (HRGN) was significantly forward in Group 2 compared to Group 3 (P-value<0.05). Conclusion: No difference in uvulo-glosso-pharyngeal dimensions were found in various vertical facial types. Differences were observed in hyoid bone position which was positioned more inferiorly in normodivergent and hyperdivergent subjects when compared to hypodivergent. Anteroposteriorly, hyoid bone was positioned more forward in hypodivergent group than in hyperdivergent.